Sorry but what's being described is not related to DMCA or copyright. If I make coolvideos.com I can say "if you upload NASA footage I will show ads on it and give that money to a random third party company" and that's not copyright infringement; public domain is inherently 'anyone can show it for any reason, even commercially'. These "copyright" claims are just Content ID where YouTube allows media rights holders to control what content shows up on YouTube - YT says 'you can only enroll videos that you own into Content ID', however, the enforcement there relies on Google only approving appropriate rights holders/production studios for Content ID. If a rights holder either has their account hacked, or they batch enroll tons of videos they haven't verified that they own the copyright to, then it'll start enforcing Content ID on those videos - and while this is bad for YouTube and its creators, it's definitely not illegal whatsoever since it isn't invoking the DMCA or any other legal action regarding copyright.

Note that, for actual DMCA claims, YouTube WILL go to bat for their creators, especially if it's an obvious case of videos falling under fair use, eg https://youtu.be/aY1CYF3MKec?t=27

In general, Content ID was created in response to Viacom dragging YouTube through court for not preemptively stopping people from uploading episodes of Spongebob. Viacom was planning to take it further up the appeal process until a settlement was reached which lead to the creation of Content ID, eg "viacom will upload copyrighted material to YouTube and YouTube will automatically scan every video to check if it violates viacom's rights". After this happened, of course, other copyright holders like AT&T (WarnerMedia)/NBC/etc and small international rights-holders weren't going to let themselves miss out on this revenue stream, so YT expanded the system to allow any rights management firm or copyright holder to use the system if they were big enough or powerful enough in their region.